FIG. 1 is a flow chart depicting a conventional method 10 for fabricating a conventional perpendicular magnetic recording (PMR) transducer. For simplicity, some steps are omitted. The conventional method 10 is used for providing side shields after formation of a PMR pole. The sidewalls of the PMR pole typically have a reverse angle. Stated differently, the top of the PMR pole is wider than the bottom. In addition, the PMR pole may have a top (trailing edge) and/or a bottom (leading edge) bevel. The leading edge bevel is formed by forming a sloped surface in the layer on which the pole is formed. Prior to formation of the side shields, a trench may be formed in a nonmagnetic layer surrounding the PMR pole or a nonmagnetic gap layer may be deposited on the PMR pole. Thus, the PMR pole is separated from the region in which the side shields will be formed by a nonmagnetic layer. The write gap may also have been deposited before the conventional method 10 starts.
A seed layer for the conventional side shield is deposited, via step 12. A photoresist layer is deposited, via step 14. For example, the photoresist may be spin coated in step 14. A conventional photoresist shield mask is formed using conventional photolithography, via step 16. Thus, portions of the photoresist layer are exposed to light. The photoresist layer may then be immersed in a developer, which removes the portions that have been exposed to light. The material(s) for the wraparound side shield are deposited, via step 18. Finally, the conventional photoresist side shield mask may be removed, via step 20.
FIGS. 2 and 3 depict side and air-bearing surface (ABS) views, respectively, of a portion of a conventional PMR transducer 30 formed using the conventional method 10. The conventional transducer 30 is shown during formation in FIG. 2. The conventional transducer 30 includes an intermediate layer 32. The intermediate layer 32 is the layer on which the pole is formed. Also shown is a bevel 33 used informing the leading edge bevel of the pole. Also shown is photoresist shield mask 36. The direction of light used in patterning the mask 36 is shown by straight arrows in FIG. 2. FIG. 3 depicts the conventional PMR transducer after fabrication is completed The Ru gap layer 34 which is deposited in the trench (not shown) is also depicted. The conventional pole 40, write gap 42 and wraparound shield 44 are also shown. For clarity, seed layer(s) are not separately depicted
Although the conventional method 10 may provide the conventional PMR transducer 30, there may be drawbacks. As shown in FIG. 2, the photoresist mask 36 may exhibit notches 38. The resist notching 38 is near the base of the photoresist mask 36. As a result, the shield plated in step 18 may have an undesirable profile. Further, the notching 38 may not be controllable, particularly in high volume processes. As a result, yield and/or performance for the conventional PMR transducer 30 may be adversely affected. Further, as can be seen in FIG. 3, resist residue 46 and 48 from the photoresist mask 36 may be present. The reverse angle of the conventional pole 40 (e.g. top being wider than the bottom) and associated structures may result in an inability to remove portions of the resist mask 36 from the shadowed regions near the bottom of the conventional pole 40. As a result, the typically organic resist residue 46 and 48 may be present in the final device. This resist residue 46 and 48 occupies regions that are desired to be part of the wraparound shield 44. Consequently, performance and/or yield may again degrade.
Accordingly, what is needed is an improved method for fabricating a side shields for transducer, such as a PMR transducer.